1. Field of the Invention
The present invention relates to a QoS management apparatus for managing the QoS (quality of service) or the CoS (class of service) for communication. In this specification, the QoS generally refers to the QoS and the CoS.
2. Description of the Prior Art
FIG. 11 is a block diagram of a conventional communication network relating to the QoS management.
As shown in FIG. 11, the service provided through an access network and a trunk network has been limited to telephone.
Therefore, the value of a requested QoS is constant for every path.
FIG. 12 is a block diagram of the configuration of the conventional QoS management apparatus. A QoS monitor is inserted into each of the paths 1, 2, 3, and 4. In an example shown in FIG. 12, a QoS is denoted by a BER (Bit Error Rate), and a BER monitor is inserted into each of the paths 1, 2, 3, and 4, and monitors the current BER of the corresponding path.
Since the value of the BER to be attained by each path is constant through a network, a BER is registered for each network.
The function of determining an operation is provided for each path, compares the value of the BER monitored by the BER monitor of the path with a value of a registered BER for each network, and performs a predetermined operation based on the comparison result.
Japanese Patent Application Laid-Open No. 6-188880 provides a system comprising a transmission server and a reception server connected to each other through a path containing an exchange unit. The transmission server and the reception server measure the state of their own system relating to the quality of the communications, and determine the band of the path depending on the measured state of their own system, thereby appropriately setting the band between the servers without a network manager. Thus, a prompt action can be taken against a sudden state change such as the concentration of cells on a certain server or a network. As a result, a system can be provided with high efficiency in communications.
The communication control apparatus disclosed by Japanese Patent Application Laid-Open No. 6-276254 (hereinafter referred to as the document) comprises a network control unit for controlling the communication depending on the type of network, a transport layer control unit for controlling the communication between end systems, and a higher order layer control unit for controlling the communication of higher order units than the transport layers, wherein a different QoS value is requested for each network, and the transport layer control unit has the function of selecting a QoS table for managing the service quality for each network and a network corresponding to the service quality requested by a higher order layer by referring to the QoS table.
According to Japanese Patent Application Laid-Open No. 9-231143, a QoS control object operating in each node monitors the resources required by the communication session existing in each node. When, for example, a QoS control message to request an increase of the resources assigned to a predetermined session is issued to each node on network from a gate-way node, the resources assigned to other communication sessions are assigned to the current communication session based on the priority of the communication session existing in each node, and the utilization state of the resources. Thus, for example, when a predetermined session temporarily transfers a large volume of data, a large volume of resources are temporarily assigned to the session, thereby effectively utilizing the resources.
However, by using the DSL (Digital Subscriber Line) technology such as an ADSL (Asynchronous Digital Subscriber Line), etc. as shown in FIG. 13, the network conventionally used only for telephone services is being used in proving various services requested by end users.
In the example shown in FIG. 13, (a) is a plan for transmitting an image (animation), (b) is a plan for telephone transmission, (c) is a plan for data transmission, and (d) is a plan for providing an Internet service.
The QoS for each of the services is represented by QoS 1, QoS 2, QoS 3, and QoS 4. The QoS 1 for animation transmission is strictly controlled against error and delay, and is demanded in high quality image transmission in real time while the QoS 1 for telephone transmission allows some errors but is strictly controlled against delay.
The QoS 3 for data transmission allows some delay, but is strictly controlled against error.
The QoS 4 for Internet provides a service is not so strict against delay or error, but is provided at a lower cost.
The xDSL shown in FIG. 13 is short for various DSLs such as an ADSL, etc.
Each service depends on each path up to the access network, and the QoS of the path should be monitored based on the value of the demanded QoS. However, such a QoS management apparatus has not been developed.
As described above, the conventional QoS management apparatus has the problem that the QoS demanded for the paths cannot be precisely satisfied when there are various types of QoS demanded for each of the paths.
The present invention has been developed to solve all the above described problems, and aims at providing the QoS management apparatus capable of precisely satisfying the QoS demanded for the paths.
The QoS management apparatus according to the present invention comprises:
a registered QoS where value of QoS requested for each path is registered;
a QoS monitor for monitoring the current value of the QoS of the path; and
means for determining an operation for determining a predetermined operation depending on the ratio of the value of the QoS monitored by the QoS monitor to the value of the QoS registered as a registered QoS.
With the configuration, the QoS management apparatus according to the present invention can precisely satisfy a demanded QoS.
That is, the QoS management apparatus of the present invention is characterized by comprising:
a registered QoS, provided for each of the plurality of paths, for storing values of QoS requested for the path;
a QoS monitor, provided for each of the plurality of paths, for monitoring the current value of the QoS of the path; and
a function of determining an operation for comparing a value of the QoS obtained by monitoring through the QoS monitor of the path with a value of the QoS registered in the registered QoS of the path, and for determining the next operation to be performed depending on the comparison result.
The operation determination function is characterized by comprising:
a timer for measuring a continuation time of the value of the QoS monitored by the QoS monitor;
a comparator for comparing the value of the QoS measured by the timer as a continuation time longer than a predetermined time; and
a function of performing an operation predetermined corresponding to the comparison result obtained by the comparator.
The QoS is characterized by being determined by a BER (Bit Error Rate), the registered QoS being a registered BER, and the QoS monitor being a BER monitor.
The QoS is characterized by being determined by a UAS (Unavailable Seconds), the registered QoS being a registered UAS, and the QoS monitor being a UAS monitor.
The QoS is characterized by being determined by a transfer delay of data packet, including CTD (Cell Transfer Delay), the registered QoS being a registered transfer delay of data packet, including registered CTD, and the QoS monitor being a monitor for a transfer delay of data packet, including a CTD monitor.
The QoS is characterized by being determined by a delay variation of data packet, including CDV (Cell Delay Variation), the registered QoS being a registered delay variation of data packet, including CDV, and the QoS monitor being a monitor for delay variation of data packet, including a CDV monitor.
The QoS is characterized by being determined by a loss of data packet, including CL (Cell Loss), the registered QoS being a registered loss of data packet, including CL, and the QoS monitor being a monitor for loss of data packet, including a CL monitor.
The operation determination function is characterized in that when the value of a QoS monitored by the QoS monitor does not satisfy the value of a QoS registered as the registered QoS, or when it is determined that there is a possibility of the monitored value not satisfying the registered value, the operation function so notifies a manager, and the manager activates a predetermined operation program.
The operation determination function is characterized in that when the value of a QoS monitored by the QoS monitor does not satisfy the value of a QoS registered as the registered QoS, or when it is determined that there is a possibility of the monitored value not satisfying the registered value, the operation function activates a predetermined operation program.
The predetermined operation program is characterized by containing a route amendment program of the path, and the route amendment program optimally utilizing network resources, and the program being executed considering the deterioration of the QoS accompanied by an amendment of a route.
A QoS management apparatus for managing a QoS of a network containing a plurality of paths for which different QoS are requested, characterized by comprising:
a function of dividing the plurality of paths into a plurality of service groups, and a service group comprising a path or a group of paths having a plurality of similar QoS requests;
a registered QoS, provided for each of the plurality of service groups, for storing the value of a QoS requested for the service group;
a QoS monitor, provided for each of the plurality of service groups, for monitoring by a time sharing system the current value of the QoS of each path belonging to the service group; and
an operation determining function, provided for each of said plurality of service groups, for comparing a value of a QoS obtained by a QoS monitor of the service group with the value of a QoS registered in a registered QoS of the service group, and for determining the next operation to be performed according to a comparison result.
The operation determination function is characterized in that when the current value of a QoS of a path in any of the service groups becomes smaller than the QoS value registered in the registered QoS of the service group, the operation determining function determines that a QoS requested for the service group is not satisfactory.
The operation determination function is characterized in that when the current values of the QoS of all paths of the service groups become lower than the QoS value registered in the registered QoS of the service group, the operation determining function determines that a QoS requested for the service group is not satisfactory.
The operation determination function is characterized in that when, in the service group, the number of the paths whose current values of the QoS are lower than the QoS value registered in the registered QoS of the service group becomes larger than the number of the paths whose current values of the QoS are lower than the QoS value registered in the registered QoS of the service group, the operation determining function determines that the QoS requested for the service group is not satisfactory.
In a QoS management apparatus for managing a QoS when various services for which different QoS is requested are transmitted through a common line, the QoS corresponding to the service is characterized by being managed depending on the value of the QoS requested for the service.